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PTHREAD_CONDATTR(3) FreeBSD Library Functions Manual PTHREAD_CONDATTR(3)
NAME
pthread_condattr_init, pthread_condattr_destroy,
pthread_condattr_getclock, pthread_condattr_setclock,
pthread_condattr_getpshared, pthread_condattr_setpshared - condition
attribute operations
LIBRARY
POSIX Threads Library (libpthread, -lpthread)
SYNOPSIS
#include <pthread.h>
int
pthread_condattr_init(pthread_condattr_t *attr);
int
pthread_condattr_destroy(pthread_condattr_t *attr);
int
pthread_condattr_getclock(pthread_condattr_t * restrict attr,
clockid_t * restrict clock_id);
int
pthread_condattr_setclock(pthread_condattr_t *attr, clockid_t clock_id);
int
pthread_condattr_getpshared(pthread_condattr_t * restrict attr,
int * restrict pshared);
int
pthread_condattr_setpshared(pthread_condattr_t *attr, int pshared);
DESCRIPTION
Condition attribute objects are used to specify parameters to
pthread_cond_init().
The pthread_condattr_init() function initializes a condition attribute
object with the default attributes.
The pthread_condattr_destroy() function destroys a condition attribute
object.
The pthread_condattr_getclock() function will put the value of the clock
attribute from attr into the memory area pointed to by clock_id. The
pthread_condattr_setclock() function will set the clock attribute of attr
to the value specified in clock_id. The clock attribute affects the
interpretation of abstime in pthread_cond_timedwait(3) and may be set to
CLOCK_REALTIME (default) or CLOCK_MONOTONIC.
The pthread_condattr_getpshared() function will put the value of the
process-shared attribute from attr into the memory area pointed to by
pshared. The pthread_condattr_setpshared() function will set the
process-shared attribute of attr to the value specified in pshared. The
argument pshared may have one of the following values:
PTHREAD_PROCESS_PRIVATE The condition variable it is attached to may
only be accessed by threads in the same process
If successful, these functions return 0. Otherwise, an error number is
returned to indicate the error.
ERRORS
The pthread_condattr_init() function will fail if:
[ENOMEM] Out of memory.
The pthread_condattr_destroy() function will fail if:
[EINVAL] Invalid value for attr.
The pthread_condattr_setclock() function will fail if:
[EINVAL] The value specified in clock_id is not one of the
allowed values.
The pthread_condattr_setpshared() function will fail if:
[EINVAL] The value specified in pshared is not one of the
allowed values.
SEE ALSO
pthread_cond_init(3), pthread_cond_timedwait(3)
STANDARDS
The pthread_condattr_init() and pthread_condattr_destroy() functions
conform to ISO/IEC 9945-1:1996 ("POSIX.1")
FreeBSD 14.0-RELEASE-p6 May 31, 2016 FreeBSD 14.0-RELEASE-p6